1. Biotechnology of Natural Products, Center of Life and Food Science Weihenstephan, Technische Universität München, Liesel-Beckmann Straße 1, 85354 Freising, Germany
2. Research Unit of Applied Botany, Department of Plant Biology, Faculty of Science, University of Dschang, Dschang P.O. Box 67, Cameroon
3. Retention of Food Quality Department, Fraunhofer Institute for Process Engineering and Packaging IVV, Giggenhauser Straße 35, 85354 Freising, Germany